188 DUBLIN UNIVERSITY 



Total number of species, 26, or about half the number recorded 

 as occurring in England and Scotland. This difference will, I trust, 

 be greatly diminished in a few years. 



Zucernariadce. 



Lucernia auricula. — Occurs on various parts of the coast. It is men- 

 tioned as found in the county of Antrim by Thompson. I have taken 

 it at Portrush, near the Giant's Causeway, and at different parts of the 

 coasts of Cork and Kerry. 



L. fascicularis. — Donaghadee (W. Templeton), along the shores of 

 Ventry Bay. It is rather common. 



L. campanulata. — Miltown Malbay (Professor Harvey); Bray (Dr. 

 Ball); Kerry (E. P.W.). 



Hydra tuba. Galway (Professor J. Eeay Greene); Dublin Bay 

 (E. P. W.). 



The Lucernariadae have such undoubted affinities to the Hydrozoa, 

 that I could not include them in my list of Zoantharia. I hope on a 

 future occasion to lay before the Association a more carefully compiled 

 list of our Irish habitats, with an account of a new species that occurred 

 to me on the shores of Yentry Bay. 



Da. Klnahan read the following paper — 



ON THE GENUS PLATrABTHBUS (BEANDT) ; WITH NOTICES OF ALLIED UNDE- 

 SCBIBED GENEBA. (WITH PLATE XIX.) 



The genus Platyarthrus, established by Brandt in 1833,* has been 

 hitherto very imperfectly characterized. "With the exception of Brandt's 

 original and imperfect description given below (vide note), there is no 

 published description of either genus or species, unless Itea crassicor- 

 nit (Koch), described in Panzer's " Fauna Germaniea." I, therefore, 

 take the opportunity of the discovery of this animal in England, by 

 the Rev. A. R. Hogan, to draw up a full description of it, and also of 

 other imperfectly known or new genera of the same great family,' Onis- 

 coidea. 



* Genus Platyarthrus (Brandt). — "Ultimus antennarum articulus, conicus, penul- 

 timus oblongus, dilatatus, compressus. Antennae sexarticulatce. 



u Platyarthrus Hoffmannseggii (nobis). Patria. Germania. Conspectus monographia 

 Crustaceorura Oniscodorum Latreillii. Mosques, p. 12." 



